How fascinating. I too have made my own solar system to augment my Planet Eben post. Loddy, have you ever seen a program called Universe Sandbox? It's at universesandbox.com, or just do a search for it. It's an astronomical program that calculates gravity. You can watch all kinds of planetary and galactic simulations and even build your own solar system and watch it work. Yours would be particularly interesting and challenging as you have several planets sharing an orbit. I think you'd like it.